Adjustable limit gauge



V 1,627,146 y 3 1927' J, c. BROOKES- ADJUSTABLE LIMIT GAUGE j-' I Filed Oct. 15 1925 Inventor Patented May 3, 1927.

;ARTHUR J'oHit orrzinnns BnooKns, of mimeiwfon rrr, ENL'AND;

Assassins Iii-iris sa es.-

tandem iiia 'ettr f5, 1525, sea-a its. arts, and ii iai Britain Jan'fiai 1, 1955,

s This invention relates to imp ove'nfei ts in limit gauges and 'consists in an improved form of gauge andme'thod of adjusting and retaining the measuri'n'g anvils "so as to give any desired gap or distance betweenthe anvils in certain predetermined steps, asfor instance steps of 0.0001 inch, means of certain fixed-size parallel anvil-pieces to gether with parallel distanceieces which can be placed between the ianVil-piecesand flat par-ans faces tonnes; oh the gauge names. The; an'vilsa-n'd eisaace pieee are h'elcl on to". the gauge frames by means" of a certain kind of screw hereinafter de scribed I a Q l II The invention is specially applicable to the well known type of gap limit gauge, used for external measurementwithin certain limits, in which one fixed is of such size as to over the were part being gauged duringmanufacture, while another fixed gap is of sifch size as must not pass" over the work; commonly known as go and notgo dimensions, respectivelyw I :I

The methodcommonly adopted for the adjustment of the measuring anvils of outside. limit gauges is that provided by justing screw devices which push. the anvi'ls forward, theanvils being usually held by separate locking devices when adjusted. Such means involve the use of additional length standards to which: the anvils are adjustedby the agency of feel ;i and the resultmay be proper or faultya'djustment ac cording tothe skillof the operator.

In this invention, I provide the. adjustment by meansof theinsertion of certain fiXed-dim-ension parallel distance-pieces in; between: fixed-dimensionparallel anvil's and the parallel faces provided on thegauge frames, and then tighteningthe anvils and distance-pieces up against the faces on the gauge frames by means of special screws. The distance between the parallel surfaces of the gauge frames is made true to a certain prescribed dimension during manufacture.

The object of the invention is to provide fixed high and low limits of any dimension, in steps of 0.0001 inch, from about 1-inch up to the practical range of these gauges; the adjustment being made Without reference to additional length standards and independent of the skill of the adjusting operator. gauge frames may be made in a convenient series of sizes, as for instance, 1, 2, 3, 4:, 5,

[vised fsnumbers To achieve this, the individual age 9; 1o, 11 aaa 12 inches, ap s any size within the practical I he distance-pieces at in the following. Serial sizes, inches r Series (III); 0.1001,. 0110 .,l003,0.100'4, 0.1905, 0.1006,; 0,1907; 0.1008, 2 0.100

I Series'fll) 0.1011; 1 02, 0.103; 0.104, 0.105, 0.10s, 0.107;, 0 .108; 0.109.

, Series (my Gill, 0:12, 0.13, 0.14, 0115,

seris; (rv)1 0; 032, 013;, eaters. I The anv lpieces a be made in thefol in inches, 0.25, 0:3,arfd 0Y5;

leaving; siZ I I I I of any other suitable 'le11gth: The

' e conveniently made 7 isses, tei gsatjeet to wean i'iruse; are p1 of the same size for replacement. I I

when mass by means and method described in patent numbered T537522, and

applications samba-ea 389L044 are 40,072,

it i's' found easily possible to malie these dis-f tan cei-pieces and anvil-pieces are 15a size within 0Z00001 'ii1'ch under conditions of Corsm'erci'al manufacture. I

The drawings" illustrate one convenient form of the limit gauges in accordance with" this invention I I Figure .1 is a side elevation of a gauge frame, with one of the holding screws of the adjustable anvils shown by partial cross section of the particular part of the gauge frame; I I j Figure 2 is'a view of same at right-angles. tonthe' View of Figure I. I I

. Eigtu-eB' is a face View of one form'of the distance-pieces, and, I

Figure 4 is an: edge view of same;

Figu re' 5 is a 'fa'ce' View of one form of the anvil-piecega'nd A Figur eB' 'sta' centralcross section of same,

showing the internally screwed portion.

In carrying the invention into effect in one convenient'manner, I provide frames at of any suitable metal, on which are provided two faces Z) and 6 Which are made truly parallel with each other and a certain basic distance apart. I

Theanvil-pieces c, 0,, c and 0 and also the distance-pieces (Z are held in Working contact with the flat faces, 6 and 6 by means of the special screws 66 The points of the screws, 6, are made with a right-hand thread and the heads, e,, have a left-hand thread. The manner of adjusting the anvilieces towards each other is as follows upposing it is required to close the anvils c and by an amount equal to 0.3003-inch; the screw would be loosened with a suitable tool and the anvil 0 be removed, distance-pieces of thicknesses 0.1003 and 0.2000-inch would then be placed over the point e of the screw which would be screwed forward by. the left-hand screw thread 6 until the point protrudes a suitable distance through and beyond the outside face of the distance-pieces; the anvilpiece'c would then be replaced and lightly tightened by hand on the screw; the screw would then be tightened by the tool and, by

virtue of these rightand left-hand screws, the anvil-pieces and distance-pieces would be held tightly in working position on the flat face 1),. The screw-thread e is made a fairly loose fit so that the anvil-pieces can accommodate themselves to lie properly flat against the other flat and parallel surfaces.

It will be understood that with the gauge frames made of a suitable form, with the anvil-pieces on the outside instead of in side the frames, this adjustment can be fitted to inside limit gauges. In this latter case, for cylindrical work, the measuring faces of the anvils would necessarily be of a spherical form.

Conveniently the distance-pieces and anvil-pieces are made by the use of apparatus forming the subject-matter of my co-pending application .for Letters Patent No. 40,072 filed the 27th day of June, 1925, and in accordance with methods described therein.

Having now described my invention what I claim as new and desireto secure by Letters Patent is V 1. An adjustable limit gauge comprising a solid frame having parallel flat surfaces spaced a fixed basic distance apart, anvilpieces of predetermined length in flat contact with said fiat surfaces and rightand left-hand screw-threaded. elements, one

thread of which engages an anvil-piece while the other engages the solid frame.

2. An adjustable limit gauge comprlsing a solid frame having parallel fiat'surfaces spaced a fixed basic distance apart, means whereby anvilpieces of predetermined length may be detachably secured in flat surface contact with said surfaces, and flat and parallel annular pieces intervening between said anvil-pieces and said surfaces.

3. An adjustable limit gauge comprising a solid frame having parallel flat surfaces thereon spaced a fixed distance apart and flat and parallel adjusting pieces associated with said surfaces, said solid frame'having screw-threaded recesses and screw-threaded elements engaging in said recesses and each having a second screw thread thereon for securing said flat parallel pieces in flat surface contact with saidsurfaces.

4. A. frame for a limit gauge having parallel flat surfaces spaced a fixed distance apart and means whereby anvil-pieces and distance-pieces may be secured in relation to said surfaces to provide a pair of gauging gaps of any desired limiting dimensions.

5. An adjustable limit gauge comprising a solid frame provided with a plurality of parallel flat surfaces spaced a fixed basic distance apart, there being perforations in the body of said fame extending through said plane surfaces and having internal screw threads therein, anvil-pieces provided with internally screw-threaded recesses and external screw-threaded elements engaging the screw threads of the perforations in the frame and the screw-threaded recesses in the anvil pieces.

6. An adjustable limit gauge comprising a solid frame provided with a plurality of parallel flat surfaces spaced a fixed basic distance apart, there being perforations in the body of said-frame extending through said plane surfaces, internal screw threads in said perforations, anvil-pieces provided with internally screw-threaded recesses and externally screw-threaded elements engaging the screw threads of the perforations in the frame and screw-threaded recesses 1n the anvil-pieces, the screw threads in the recess in the anvil and the screw threads in the perforation in the frame being of opposite senses. I In testimony whereof I have signed my name to this specification. ARTHURJOHN CHARLES BROOKES. 

